acl_threshold.h

/* * Copyright (c) 2000-2004 Apple Computer, Inc. All Rights Reserved. * * @APPLE_LICENSE_HEADER_START@ * * This file contains Original Code and/or Modifications of Original Code * as defined in and that are subject to the Apple Public Source License * Version 2.0 (the 'License'). You may not use this file except in * compliance with the License. Please obtain a copy of the License at * http://www.opensource.apple.com/apsl/ and read it before using this * file. * * The Original Code and all software distributed under the License are * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. * Please see the License for the specific language governing rights and * limitations under the License. * * @APPLE_LICENSE_HEADER_END@ *///// acl_threshold - Threshold-based group ACL subjects.//// This subject type implements threshold (k of n) subjects as per CSSM standard.// Subsubjects are stored and evaluated in the order received. Any subsubject// is presented with all subsamples of the corresponding threshold sample, but// not any other samples possibly present in the credentials. Subsubject evaluation// stops as soon as the threshold is satisfied, or as soon as it becomes numerically// impossible to satisfy the threshold with future matches.// Note that this subject will reject out of hand any threshold sample that// contains more than <n> subsamples. This defeats "sample stuffing" attacks// where the attacker provides thousands of samples in the hope that some may// match by accident. It will however accept threshold samples with fewer than// <n> subsamples, as long as there are at least <k> subsamples.//#ifndef _ACL_THRESHOLD#define _ACL_THRESHOLD#include <security_cdsa_utilities/cssmacl.h>#include <vector>namespace Security {
class ThresholdAclSubject : public SimpleAclSubject {
typedef ObjectAcl::AclSubjectPointer AclSubjectPointer;
typedef vector<AclSubjectPointer> AclSubjectVector;
public:
bool validate(const AclValidationContext &baseCtx, const TypedList &sample) const;
CssmList toList(Allocator &alloc) const;
ThresholdAclSubject(uint32 n, uint32 k, const AclSubjectVector &subSubjects);
void exportBlob(Writer::Counter &pub, Writer::Counter &priv);
void exportBlob(Writer &pub, Writer &priv);
IFDUMP(void debugDump() const);
class Maker : public AclSubject::Maker {
public:
Maker() : AclSubject::Maker(CSSM_ACL_SUBJECT_TYPE_THRESHOLD) { }
ThresholdAclSubject *make(const TypedList &list) const;
ThresholdAclSubject *make(Version, Reader &pub, Reader &priv) const;
};
private:
uint32 minimumNeeded; // number of matches needed
uint32 totalSubjects; // number of subSubjects
AclSubjectVector elements; // sub-subject vectortemplate <class Action>
void ThresholdAclSubject::exportBlobForm(Action &pub, Action &priv);
};
} // namespace Security#endif //_ACL_THRESHOLD